Spa



FIG. 1 is a perspective view of the spa of the invention;

FIG. 2 is a top and left side perspective view of the spa illustrated in FIG. 1;

FIG. 3 is a top plan view of the spa illustrated in FIG. 1;

FIG. 4 is a front elevation of the spa illustrated in FIG. 1;

FIG. 5 is a left side elevation view of the spa illustrated in FIG. 1, the right side elevation view being identical; and,

FIG. 6 is a rear elevation view of the spa illustrated in FIG. 1.

The broken lines are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a spa, as shown and described. 